Level.



A. SVENNEBY.

Patented Aug. 20, 1912.

a emu;

Suva/tow AUGUST SVENNEBY, OF ALBANY, OREGON.

LEVEL.

Specification of Letters Patent.

Application filed February 14, 1912.

Patented Aug. 20, 1912.

Serial No. 677,432.

To all whom it may concern Be it known that I, AUcUs'r SVENNEBY,

a citizen of the United States, residing at Albany, in the county of Linn and State of Oregon, have invented certain new and useful Improvements in Levels, of which the following is a specification.

This invention has for its object to provide a spirit level having a longitudinally extensible stock so that its length may be increased.

A further object of the invention is to provide a novel and improved mounting for the bubble-tube, in order that it may be set to different positions relative to a graduated dial.

With these objects in view, the invention consists in a combination and arrangement of parts to be hereinafter described and claimed, reference being had to the accompanying drawing in which- Figure 1 is a side elevation of the level, and Fig. 2 is a cross-section on the line 22 of Fig. 1.

Referring specifically to the drawing, the stock 9 of the instrument is a straight bar which is substantially T-shaped in cross section. At the head of the bar, in each side thereof is a downturned flange 10 which is spaced from the web 11 of the bar so as to form a vertical slot in which an extension piece 12 is slidably mounted. The upper end of the slot is enlarged transversely and the extension piece is formed with a head or enlargement 13 conforming thereto, whereby vertical displacement is prevented. The flanges 10 do not extend down as far as the base of the web 11 but are spaced some distance therefrom for a purpose to be presently described. The slots in which the extension pieces are mounted are parallel and extend throughout the entire length of the stock. One of the extension pieces is adapted to be extended from one end of the stock, and the other extension piece from the other end, and they are locked in adjusted position by set screws 14 threaded through the head of the stock.

Each extension piece 12 has an outstanding horizontal base flange 15, the bottom of which latter is flush with the bottom of the web 11 so that a firm support for the instrument may be had. To the outer end of each extension piece is secured a foot 16, the latter being secured to the inner face of the extension piece by screws 17, the extension piece having end slots 18 through which the screws pass. The foot also serves as a stop to limit the inward movement of the extension piece by abutting against the end of the stock. The base flanges 15 of the extension pieces are located beneath the flanges 10 and spaced therefrom, and carry bowed springs 19 which are in contact with the bottom edge of said flanges 10, said springs serving to hold the extension pieces when the set screws 14: are loosened.

By the structure herein described, an extensible level is had which can be easily adjusted, and which stands solid when in use, whether the extension pieces are extended or retracted.

The support for the bubble-tube 20 is a block 21 which is rigidly secured to the upper edge or top of the stock, to which latter is also secured a strap 22 which extends in the direction of the length of the stock'and is spaced therefrom, the ends of the strap being downturned and secured by screws or other suitable fastening means to the stock. The block is mounted midway between the ends of the stock and is located between the top thereof and the strap. At the top and the bottom of the block are integral outstanding flanges 23 through which screws or other suitable fastening means 23 pass, whereby the block is rigidly secured on the stock. The block 21 has a transverse circular opening in which is mounted a ring 24c which carries the bubble-tube 20. The outer periphery of the ring is beveled and the wall of the opening in which it seats is correspondingly beveled. To one of the faces of the block 21 is secured a dial-plate 25 having a circular opening through which the bubble-tube is visible. The dial-plate overlaps the widest end of the ring 24- so as to prevent it from working out of the opening in the block, the bevel of the ring preventing it from working out of the opening at the other end. On the dial-plate 25, adjacent to the opening therein, are graduations 26, and the ring 24 is loose in the opening of the block 21 so that it may be rotated and placed in different positions relatively to said graduations, in view of which the degree of inclination or deviation from the horizontal of the surface to which the instrument is applied may be readily obtained The ring can also be rotated to place the bubble-tube perpendicular to the stock in order that the instrument may be used vertically or as a plumb level. The ring which carries the bubble-tube is locked by means of set screws 27 threaded through the block 21. The strap 22 also serves as a handle, and thus facilitates the handling of the instru-' ment.

I claim:

1. A level comprising a stock having parallel vertical slots opening downward and extending lengthwise of the stock, the upper ends of the slots being enlarged transversely, and extension pieces mounted in said slots and adapted to be projected from the ends of the stock, said extension pieces having enlarged top portions corresponding to the enlarged portions of the slots, and the base of the extension pieces having outstanding flanges which are flush with the base of the stock.

2. A level comprising a stock having de pending side flanges at the top, said flanges extending in the direction of the length of the stock and being spaced from the sides thereof to form longitudinal slots, extension pieces mounted in the slots and having out standing base flanges which are flush with the base of the stock and spaced from the aforesaid flanges of the stock, and bowed springs interposed between said flanges.

8. A level comprising a stock, a block mounted thereon and having a circular opening the wall of which is beveled a ring rotatably mounted in said opening and having a beveled outer periphery to conform to the bevel of the opening, a bubble-tube car-- ried by the ring, a plate secured to the block over the larger end of the ring, said plate having an opening through which the bub- .ble-tube is visible, and means for locking the ring in the opening of the block.

In testlmony whereof I aifix my slgnature in presence of two witnesses.

AUGUST SVENNEBY. lVitnesses Gno. V. VRIGHT, NoEL'B. MARTIN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

